account for network fees in sales without platform fees (no buffer)

items/forms.py

@@ -13,7 +13,7 @@ class CreateItemForm(forms.ModelForm):
         help_texts = {
             'name': 'Use a succinct name for your item. Don\'t be spammy or obscene.',
             'description': 'Describe the condition of the item and any important information. Try to refrain from sharing personally identifiable information like phone numbers or social media links.',
-            'whereabouts': 'A simple pointer to your general region - a nearby ZIP code or capital city would be perfect.',
+            'whereabouts': 'A simple pointer to your general region - a nearby capital city and your state would be perfect.',
             'ask_price_xmr': 'How many moneroj do you want for your item?',
             'payout_address': 'A Monero wallet address where funds will be sent after sale is confirmed.',
         }

sales/migrations/0004_auto_20200113_2127.py

@@ -0,0 +1,23 @@
+# Generated by Django 2.2.8 on 2020-01-13 21:27
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('sales', '0003_itemsale_sale_cancelled'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='itemsale',
+            name='network_fee_xmr',
+            field=models.FloatField(default=0.0),
+        ),
+        migrations.AddField(
+            model_name='itemsale',
+            name='seller_payout_transaction',
+            field=models.CharField(blank=True, max_length=150),
+        ),
+    ]

sales/models.py

@@ -12,6 +12,8 @@ class ItemSale(models.Model):
     escrow_account_index = models.IntegerField()
     agreed_price_xmr = models.FloatField()
     platform_fee_xmr = models.FloatField()
+    network_fee_xmr = models.FloatField(default=0.0)
+    seller_payout_transaction = models.CharField(max_length=150, blank=True)
     expected_payment_xmr = models.FloatField()
     received_payment_xmr = models.FloatField(default=0.0)
     escrow_period_days = models.PositiveSmallIntegerField(default=settings.ESCROW_PERIOD_DAYS)

sales/tasks.py

@@ -122,7 +122,7 @@ def poll_for_buyer_escrow_payments():
         sale.save()
 
 
-@periodic_task(crontab(minute='*/5'))
+@periodic_task(crontab(minute='*'))
 def pay_sellers_on_sold_items():
     aw = AuctionWallet()
     if aw.connected is False:
@@ -134,12 +134,22 @@ def pay_sellers_on_sold_items():
         # Take platform fees from the sale - the 50:50 split between buyer/seller
         sale_total = sale.agreed_price_xmr - sale.platform_fee_xmr
         sale_account = aw.wallet.accounts[sale.escrow_account_index]
-        logger.info(f'[INFO] Sending {sale_total} XMR from wallet account #{sale.escrow_account_index} to item owner\'s payout address for sale #{sale.id}.')
+
-        if sale_account.balances()[1] > Decimal(sale.agreed_price_xmr):
+        if sale_account.balances()[1] >= Decimal(sale.agreed_price_xmr):
             try:
-                sale_account.transfer(
+                # Construct a transaction so we can get current fee and subtract from the total
-                    sale.item.payout_address, sale_total
+                _tx = sale_account.transfer(
+                    sale.item.payout_address, Decimal(.01), relay=False
                 )
+                new_total = sale_total - float(_tx[0].fee)
+
+                logger.info(f'[INFO] Sending {new_total} XMR from wallet account #{sale.escrow_account_index} to item owner\'s payout address for sale #{sale.id}.')
+                # Make the transaction with network fee removed
+                tx = sale_account.transfer(
+                    sale.item.payout_address, new_total, relay=True
+                )
+                sale.network_fee_xmr = _tx[0].fee
+                sale.seller_payout_transaction = tx[0]
                 sale.seller_paid = True
                 sale.escrow_complete = True
                 sale.save()
@@ -175,9 +185,13 @@ def pay_platform_on_sold_items():
         sale_account = aw.wallet.accounts[sale.escrow_account_index]
         bal = sale_account.balances()[1]
         if bal >= 0:
-            logger.info(f'[INFO] Getting platform fees of {bal} XMR')
             try:
-                sale_account.sweep_all(aof)
+                if settings.PLATFORM_FEE_PERCENT > 0:
+                    logger.info(f'[INFO] Getting platform fees of {bal} XMR')
+                    sale_account.sweep_all(aof)
+                else:
+                    logging.info('No platform fees are set - proceeding without taking fees.')
+
                 sale.platform_paid = True
                 sale.sale_finalized = True
                 sale.save()

sales/views.py

@@ -35,6 +35,9 @@ def get_sale(request, sale_id):
     address_qr = qrcode_make(qr_uri).save(_address_qr)
     total_seller_payout = sale.agreed_price_xmr - sale.platform_fee_xmr
 
+    if sale.network_fee_xmr:
+        total_seller_payout = total_seller_payout - sale.network_fee_xmr
+
     context = {
         'sale': sale,
         'qrcode': b64encode(_address_qr.getvalue()).decode(),

web/templates/sales/get_sale.html

@@ -116,11 +116,13 @@
       {% elif sale.item_received %}
       <p class="sale-info">Hey {{ sale.item.owner.username }},</p>
       <p class="sale-info">The buyer confirmed receipt of their shipment which means things worked out. It's time for you to get paid!</p>
-      <p class="sale-info">Your payout address provided during item creation will be paid the accepted bid amount out of the escrow wallet.</p>
+      <p class="sale-info">Your payout address provided during item creation will be paid the accepted bid amount out of the escrow wallet. <strong>Please note, transaction fees will come out of the payout total.</strong></p>
       <p class="sale-info"><strong>Accepted Bid (XMR)</strong>:  {{ sale.bid.bid_price_xmr }}</p>
       <p class="sale-info"><strong>Platform Fee (XMR)</strong>:  {{ sale.platform_fee_xmr }}</p>
+      <p class="sale-info"><strong>Network Fee (XMR)</strong>:  {{ sale.network_fee_xmr }}</p>
       <p class="sale-info"><strong>Total Payout (XMR)</strong>:  {{ total_seller_payout }}</p>
       <p class="sale-info"><strong>Payout Address</strong>: {{ sale.item.payout_address }}</p>
+      <p class="sale-info"><strong>Payout Transaction ID</strong>: {{ sale.seller_payout_transaction }}</p>
       <br>
       <p class="sale-info">If you found the site useful and had a good experience, please consider donating to the developer address provided at the bottom of the page.</p>
       <p class="sale-info">Thanks for using {{ site_meta.name }}!</p>

web/templates/sales/notify/sale_completed/seller/body.txt

@@ -1,6 +1,6 @@
 Congratulations {{ sale.item.owner }},
 
-The sale of your item, "{{ sale.item.name }}" (#{{ sale.item.id }}), has concluded. The agreed upon bid price has been transferred to the payout address provided when posting the item.
+The sale of your item, "{{ sale.item.name }}" (#{{ sale.item.id }}), has concluded. The agreed upon bid price minus any network fees has been transferred to the payout address provided when posting the item.
 
 In a few more minutes post-processing will complete, the platform will receive it's fees, and the sale, item, and bids will all be removed from the system. If your fees were waived, please consider donating to the development fund. The address is at the bottom of the {{ site_name }} site pages.